Fractional circular polarization profiles V/I for the core and near-wing region of the K (upper panel) and 8542 Å (lower panel) lines. The emergent profiles are shown for a line of sight with μ = 0.1. The imposed 200 G magnetic field is horizontal, height-independent, and quasi-parallel (μ_B = 0,  μ = 0.1) to the observer. The curves represent the synthetic profiles with (solid black) and without (dashed red) atomic level polarization, and the WFA result (dotted blue).